Grades of up to 6.16% Li2O from latest laboratory flotation testwork reaffirms the quality and commercial potential of the Seymour Lake Lithium ProjectPerth, Aug 31, 2017 AEST (ABN Newswire) - Diversified minerals explorer and developer Ardiden Limited (ASX:ADV) is pleased to advise that it has received further highly encouraging metallurgical testwork results from Independent Metallurgical Operations (IMO), based in Perth, Western Australia, for a composite bulk sample obtained from the North Aubry prospect at its 100%-owned Seymour Lake Lithium Project in Ontario.
- High-grade lithium concentrates of up to 6.16% Li2O produced from a single stage flotation test on drill core samples from the Seymour Lake Lithium Project in Canada.
- High Li2O recovery of 76% achieved at a coarse grind size of 150 micron m, with the testwork again confirming that the spodumene particles are well-liberated at a very coarse particle size.
- Variability testwork currently underway with a range of drilling samples from the North Aubry prospect.
- Testwork is continuing to develop a suitable commercial processing flowsheet.
Commenting on the results, Ardiden Technical Director, Dr Michelle Li said:
"These initial metallurgical test results are very encouraging and continue to demonstrate that the spodumene material from bulk samples taken from Seymour Lake liberates very well at a coarse grind size by using simple and proven and processes such as gravity or flotation to obtain high grade lithium concentrate."
"These results further confirm the very high-quality nature of the spodumene material found at Seymour Lake and give us confidence in the commercial potential of the project. We are looking forward to receiving the rest of the testwork results, which will allow us to finalise a commercial processing flowsheet for the project."
Ardiden has previously reported results from metallurgical and mineralogical results on the Seymour Lake spodumene samples, including the announcement of 9 February 2017, which outlined excellent results from initial Heavy Liquid Separation (HLS) testwork - including the production of extremely high-grade lithium concentrate grading up to 7.73% Li2O. This was followed by the announcement of results from Dense Media Separation (DMS) testwork on 26 April 2017, which produced high-grade lithium concentrate grading up to 7.23% Li2O.
These initial metallurgical results were supported by the announcement of mineralogy testwork on 12 April 2017 which demonstrated that the spodumene cleavage fragments are in excess of 600micron, confirming the presence of liberated and coarse spodumene particles with XRD/SEM tests confirming only trace amounts of deleterious minerals.
These combined results confirm the high quality of the Seymour Lake spodumene ore and bodes well for the recovery of lithium concentrate using relative simple recovery processes.
The previous initial laboratory testwork results outlined above, have clearly demonstrated that additional processing techniques such as flotation and acid leaching have not been required to produce a high-grade lithium concentrate, confirming the high-quality nature of the low-iron spodumene located at the Seymour Lake Lithium Project.
However, in order for Ardiden to obtain a true understanding of the physical properties of the Seymour Lake spodumene material at a commercial scale and identify a full scope of potential end-users, a full range of metallurgical testwork is required to be completed, including flotation testwork.
A single flotation test conducted on a spodumene sample completed at the grind size (P80 = 150 micron m), produced a high-grade concentrate of 6.16% Li2O at a relatively high recovery rate 75.7%.
The flotation tests were conducted on the composite sample of drill cores obtained from diamond drill holes SL-09-33, SL-09-27A and SL-09-45.
The grade recovery curve for the flotation method is shown below in Figure 1 (see link below). Ardiden confirms that further tests may be conducted to assess the potential to increase recovery rates. However, further flotation tests are not a high priority given the strong performance of the DMS and HLS techniques, and this extraction process is unlikely to be used by the Company in a commercial production scenario of lithium concentrate at Seymour Lake.
Ardiden confirms the presence of micas in the spodumene concentrate sample at the coarse crushing size of 9.5mm. Ardiden is currently undertaking additional testwork on the micas to develop a better understanding of this material and whether it could be removed to improve the Li2O concentrate grade.
Ardiden considers these current laboratory flotation test results to be extremely encouraging and the results from the drill core samples provided to IMO again indicate that the spodumene particles liberate at a coarse particle size.
As previously advised on 27 July 2017, additional and more comprehensive metallurgical testwork is being completed on a bulk sample of spodumene ore with the assistance of Ardiden's strategic partner, Yantai Jinyuan Mining Machinery Co., Ltd. These tests will assist Ardiden to identify the most appropriate process to recover Li2O from the spodumene ore at the Seymour Lake Project.
The metallurgical testwork program on the bulk sample will assist Ardiden and Yantai in the development of the lithium processing facility and to obtain a better understanding of how the Seymour Lake spodumene performs in the larger scale processing and will provide guidance and support for the project feasibility study.
The metallurgical testwork program will allow Ardiden to investigate the lithium recovery and various extraction process options including gravity and flotation separation processes to develop an optimum process flowsheet for the project.
The composite sample was obtained by combining drill cores from three separate locations across the North Aubry Prospect (refer to Figure 3 in the link below).
Ardiden confirms the laboratory flotation tests has again provided additional specific data which helps to determine the physical properties of samples and provides guidance with characterising the parameters of ore processing and to predict the expected recovery rates of lithium concentrate. The interpolated recoveries and Li2O concentrate grade from the flotation testwork conducted on the samples are tabulated below in Table 1 (see link below).
Ardiden notes these are highly encouraging results for preliminary flotation assessment. Metallurgical variability of the deposit will be investigated in future test work programs. These latest test results are another important step forward to better understanding the potential commercial viability of the Seymour Lake Lithium Project and is a key advancement to the next stage of development.
The next phase of the metallurgical testwork program will allow Ardiden and Yantai to further investigate the lithium recovery and various extraction process options including gravity and flotation separation processes to develop an optimum process flowsheet for the commercial production of Lithium concentrate at the Seymour Lake project.
Ardiden looks forward to providing further updates as they come to hand.
To view tables and figures, please visit:
About Ardiden Ltd
Ardiden Limited (ASX:ADV) is an emerging international strategic metals company which is focused on the exploration, evaluation and development of four 100 per cent owned projects located in the established mining jurisdiction of Ontario, Canada.